The present invention relates, in general, to electronics, and more particularly, to methods of forming semiconductor devices and structure.
In the past, the semiconductor industry utilized various methods and structures to produce power metal oxide semiconductor field effect transistor (power MOSFET) driver circuits there were utilized to drive the power MOSFETs of a power supply system. Typically, one power MOSFET was connected to supply charging voltage to an inductor and a second power MOSFET was connected to discharge the inductor. The second power MOSFET often was referred to as a synchronous rectifier. The power MOSFET typically had a large gate capacitance which had to be driven in order to enable and disable the transistor. The driver circuit had large output transistors in order to supply sufficient drive current to charge and discharge the capacitances of the power MOSFETs. The driver circuit generally received pulse width modulated (PWM) control signals from a PWM controller and drove the appropriate transistors. One example of such a power MOSFET driver circuit was an NCP5355 that was produced by ON Semiconductor of Phoenix Ariz. In some cases, the power supply voltage utilized by the individual drivers of the driver circuit did not provide the most efficient operation.
Accordingly, it is desirable to have a power MOSFET driver that utilizes a power supply voltage that provides efficient operation of the power supply system.
For simplicity and clarity of illustration, elements in the figures are not necessarily to scale, and the same reference numbers in different figures denote the same elements. Additionally, descriptions and details of well-known steps and elements are omitted for simplicity of the description. As used herein current carrying electrode means an element of a device that carries current through the device such as a source or a drain of an MOS transistor or an emitter or a collector of a bipolar transistor or a cathode or anode of a diode, and a control electrode means an element of the device that controls current through the device such as a gate of an MOS transistor or a base of a bipolar transistor. Although the devices are explained herein as certain N-channel or P-Channel devices, a person of ordinary skill in the art will appreciate that complementary devices are also possible in accordance with the present invention.